| [GMCnet] Multiviscosity oils [message #365336] |
Sat, 10 July 2021 11:53 |
Emery Stora
Messages: 959
Registered: January 2011
Karma:
|
Senior Member |
|
|
I have recently been asked questions about multi viscosity oils and viscosity modifiers. Specifically how do synthetics get to be multi-viscosity without reducing the lubrication content and why you don’t see single grade synthetics.
I wrote a Tech Bulletin when I was the Tech VP of Western States GMC club back about 20 year ago and the information is still good. You can find it at
http://www.gmcws.org/techcenter/01-08tc34.html
The VI Improvers (viscosity index improvers) do not generally have much lubricity so one does not want to purchase an oil which uses a high percentage of them. That is why I mention in the Tech bulletin that most auto manufacturers no longer recommend 10W40 oils (mineral oils - not synthetic).
It turns out that most synthetics exhibit a multi-vis nature without adding VI Improvers. Mobil1 doesn't use any in their 5w30 or 10w30 oil and very little in the 15w50 so you don't see degradation of lubricating properties as you might with a 10W40 mineral oil. Since the product is a multi-vis without using additives they don't label it as a single grade synthetic.
--
Emery Stora
emerystora@mac.com
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
|
|
|
|
GMCforum
Search
Help
Register
Login
Home
